Laparoscopic or endoscopic surgery, requiring only a small opening in a patient to perform a medical procedure, is a great advance in medical science. Patients endure much less pain and suffering, because the surgeon is able to use a much smaller cut or opening, in order to perform a given procedure. These advances have occurred in almost all branches of surgery, including gynecological, urological, and vascular surgery, even extending to neurosurgery. The surgeon is able to perform these procedures by remotely manipulating a great many instruments. Of course, the surgeon must be able to see what he or she is doing, so that he or she is able to control the instruments and to correctly and efficiently perform the procedure in question.
Medical imaging techniques have thus struggled to keep pace with the advances in surgery, especially the minimally-invasive techniques that allow these procedures. Thus, a large variety of endoscopes, ureteroscopes, ultrasound machines, and fluoroscopes, along with ultrasound machines, magnetic resonance (MR) imagers, and the like, have arisen and are being used by surgeons and medical professionals to guide their accomplishment of such procedures. Those skilled in the medical arts have especially welcomed ultrasound imaging techniques, which are enhanced through the use of echogenic devices. Echogenic devices are devices whose surface has been “dimpled” or roughened in a particular manner to enhance their detection by ultrasound equipment.
Echogenic surfaces, as described in U.S. Pat. Nos. 5,981,997 and 5,201,314, are typically hemispherical or curved, allowing distortion of the sound wave as it reflects from the surface. This interference is then detected by the ultrasound machine, and the pattern of interference is interpreted as an image. In this manner, catheters, needles, and a great variety of objects may be inserted into a human or animal body, and their presence and location detected.
At least one difficulty with echogenic devices, however, is the relatively imprecise image that is available to the surgeon or other medical professional. A better way to form a medical device with a detectable or echogenic surface is needed. A medical device with an echogenic surface that may be more precisely located within a patient is also desired.